On the integration of personality assessment methods: the Rorschach and MMPI

Despite being the most studied and used personality assessment tools, data from the Rorschach and MMPI generally disagree (Archer & Krishnamurthy, 1993a, 1993b). Independence is proposed to result from at least 3 factors: (a) the methods tap unique levels of personality, (b) personality has a complex organization, and (c) response styles generate considerable method variance that must be considered in nomothetic research. These ideas led to 5 hypotheses, each of which received support. Rorschach and MMPI response styles are uncorrelated, although response styles are quite consistent within a method family. MMPI-2 and Rorschach constructs of dysphoria, psychosis, or wariness are uncorrelated when response styles are ignored. However, robust convergent validity is evident when patients have similar response styles on each method (e.g., for dysphoria, M r = .59) and dysphoria is expressed in opposing ways on each method when response styles are discordant (i.e., M r = -.54). Data from the latter analyses were correlated with genuine clinical phenomena and implications were discussed for clinical practice and research.